It is common practice to make use of pens having numerous gates for the containment and handling of animals such as hogs and the like. The gates generally include a panel element which is pivotally mounted between a pair of posts with a locking device coupled thereto to prevent the gate from being opened when unattended such that the animals are prevented from escaping the pen. The present invention is concerned with certain improvements to a gate and gate post assembly for use with animal containment pens.